INSIZE Electronic Deep Throat Micrometer This Electronic Deep Throat Micrometer from INSIZE is the perfect gage for measuring Disk Brakes. The 3.465" Deep Throat provides lots of room for measuring applications that a standard 1" micrometer just can't reach. Features Include... 0.3"-1.3" / 7.6-33mm Measuring Range 0.00005" / 0.001mm Resolution 0.0002" / 0.005mm Accuracy 3.465" Deep Throat Flat Carbide Face on Anvil & Pointed Spindle Enamel finish frame. Ratchet Stop. Spindle Lock Inch/Metric absolute and relative measuring conversion Spindle diameter: 0.250" Furnished in fitted case